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191.
Sensory and Physicochemical Studies of Thermally Micronized Chickpea (Cicer arietinum) and Green Lentil (Lens culinaris) Flours as Binders in Low‐Fat Beef Burgers 下载免费PDF全文
Shiva Shariati‐Ievari Donna Ryland Andrea Edel Tiffany Nicholson Miyoung Suh Michel Aliani 《Journal of food science》2016,81(5):S1230-S1242
Pulses are known to be nutritious foods but are susceptible to oxidation due to the reaction of lipoxygenase (LOX) with linolenic and linoleic acids which can lead to off flavors caused by the formation of volatile organic compounds (VOCs). Infrared micronization at 130 and 150 °C was investigated as a heat treatment to determine its effect on LOX activity and VOCs of chickpea and green lentil flour. The pulse flours were added to low‐fat beef burgers at 6% and measured for consumer acceptability and physicochemical properties. Micronization at 130 °C significantly decreased LOX activity for both flours. The lentil flour micronized at 150 °C showed a further significant decrease in LOX activity similar to that of the chickpea flour at 150 °C. The lowering of VOCs was accomplished more successfully with micronization at 130 °C for chickpea flour while micronization at 150 °C for the green lentil flour was more effective. Micronization minimally affected the characteristic fatty acid content in each flour but significantly increased omega‐3 and n‐6 fatty acids at 150 °C in burgers with lentil and chickpea flours, respectively. Burgers with green lentil flour micronized at 130 and 150 °C, and chickpea flour micronized at 150 °C were positively associated with acceptability. Micronization did not affect the shear force and cooking losses of the burgers made with both flours. Formulation of low‐fat beef burgers containing 6% micronized gluten‐free binder made from lentil and chickpea flour is possible based on favorable results for physicochemical properties and consumer acceptability. 相似文献
192.
Eugen Michel 《Holz als Roh- und Werkstoff》1938,1(9):332-335
Zusammenfassung Die gro?e Bedeutung, die dem Holz für die Errichtung von Tragwerken wie auch für die Ausstattung von R?umen zukommt, rechtfertigt
es, sich einmal die akustischen Eigenschaften dieses Baustoffes zu vergegenw?rtigen.
Grunds?tzlich handelt es sich dabei um zweierlei Dinge, n?mlich raumakustisch um die Einwirkung auf die H?rsamkeit, d. h.
um die Beeinflussung von Schall, der in einem Raum erzeugt wird und in diesem selbst verl?uft, und dann bauakustisch um die
D?mmung, d. h. um die F?higkeit, einen auftreffenden Schall zurückzuhalten, ihn nicht nach au?en, also in andere R?ume oder
ins Freie dringen zu lassen. 相似文献
193.
Zhenzhou Zhu Jianquan Luo Luhui Ding Olivier Bals Michel Y. Jaffrin Eugene Vorobiev 《Journal of food engineering》2013
Clarification is the first step of inulin production from chicory juice, and membrane filtration as an alternative can greatly simplify this process, increase juice yield, improve product quality, and reduce the cost and waste volume. In this study, a rotating disk module (RDM) was used to investigate the clarification of chicory juice by four micro- and ultrafiltration membranes. Compared with dead end filtration, the RDM had a much higher permeate flux and product quality. High rotating speeds produced high permeate fluxes and reduced flux decline, because of the strong back transport of foulant from fouling layer to feed solution. At high rotating speeds of 1500–2000 rpm, the permeate flux increased with membrane pore size and transmembrane pressure (TMP), while at low rotating speeds (<1000 rpm), permeate flux was independent of membrane type and TMP due to a thick deposited fouling layer as a dominant filtration resistance, while carbohydrate transmission decreased at higher TMP because of denser cake layer as an additional selective membrane. The highest carbohydrate transmission (∼98%) and desirable permeate turbidity (2.4 NTU) was obtained at a TMP of 75 kPa and a rotating speed of 2000 rpm for FSM0.45PP membrane. With the RDM, the Volume Reduction Ratio (VRR) could reach 10 with a high permeate flux (106 L m−2 h−1) in the concentration test, and permeate was still rich in carbohydrate and well clarified. Chemical cleaning with 0.5% P3-ultrasil 10 detergent solution was able to recover 90% water flux of fouled membrane. 相似文献
194.
Biodegradable Ethylene‐Bis(Propyl)Disulfide‐Based Periodic Mesoporous Organosilica Nanorods and Nanospheres for Efficient In‐Vitro Drug Delivery 下载免费PDF全文
195.
196.
Mice Fed a High‐Cholesterol Diet Supplemented with Quercetin‐3‐Glucoside Show Attenuated Hyperlipidemia and Hyperinsulinemia Associated with Differential Regulation of PCSK9 and LDLR in their Liver and Pancreas 下载免费PDF全文
197.
Effects of deBDE and PCB-126 on hepatic concentrations of PBDEs and methoxy-PBDEs in Atlantic tomcod 总被引:1,自引:0,他引:1
The biotransformation of high bromosubstituted polybrominated diphenyl ethers (PBDEs) congeners contained in a commercial deca mixture (DeBDE) is of environmental concern because it might lead to the increase of toxic low brominated PBDEs in biota. A few studies have reported that freshwater fish dietary exposed to DeBDE or its main constituent, decabrominated PBDE congener (BDE-209), had their tissues enriched with PBDEs not initially present in fish or feed. In the present study, Atlantic tomcod (Microgadus tomcod) were intraperitoneally (IP) injected with DeBDE to assess hepatic concentration changes of PBDEs and methoxy polybrominated diphenyl ethers (MeO-PBDEs) in a marine fish species. Tomcod were also IP injected with polychlorinated biphenyl (PCB)-126 to evaluate the impact of cytochrome P4501A (CYP1A) induction on the biotransformation of injected PBDEs contained in DeBDE and PBDEs initially present in fish. Besides BDE-209, concentrations of BDE-203 and three other unidentified octabrominated PBDEs and the nonabrominated PBDEs (BDE-206, -207, and -208) were enriched in the liver of fish injected with DeBDE. All these PBDE congeners, essentially absent in control fish, were identified as impurities in DeBDE, and, thus, their presence could not be attributed exclusivelyto biotransformation. Despite a 4.3times increase of EROD activity in the liver of tomcod injected with both PCB-126 and DeBDE, compared to DeBDE alone, no further increases of PBDE hepatic concentrations were observed. However, depleted concentrations of BDE-17 (x 1.5) and 6-MeO-BDE-47 (x 1.4) were found in fish IP injected with DeBDE compared to control fish, likely due to activated hepatic metabolic enzymes other than CYP1A. Fish injected with PCB-126 showed an even more significant depletion of BDE-17 hepatic concentrations (x 3.5) than the one associated with the DeBDE treatment and a significantly lower proportion of fish with quantifiable concentrations of BDE-203. Thus, CYP1A inducers can promote the biotransformation of PBDEs in fish liver. This study shows that exposure of fish to DeBDE is expected to result in the enrichment of high brominated PBDEs in fish liver and that metabolic activities in fish can affect their PBDE bioaccumulation pattern and possibly the toxicity of PBDEs to fish. 相似文献
198.
Cavitation erosion during the incubation period was investigated via pitting tests conducted on three different materials: an Aluminum alloy, a Nickel Aluminum Bronze alloy and a Duplex Stainless Steel. Pitting tests were conducted in a cavitation tunnel in the velocity range 45–90 m/s at a constant cavitation number. The test section was made of a straight nozzle 16 mm in diameter discharged into the radial 2.5 mm space between two flat walls. Cavitation appears in the form of a toroidal cavity attached to the nozzle exit and damage on the samples facing the nozzle is concentrated in a circular ring centered in the cavity closure region. The exposure time was adjusted to avoid pit overlapping. The material surface was examined using a conventional contact profilometer which allowed us to identify the pits, count them, and measure their main characteristics such as depth, surface area, and volume. From these the pitting rate, the coverage rate, and the depth of deformation rate were defined. Pits were classified according to their diameter. For all materials and operating conditions, pitting rate appears to follow an exponential law in relation to the pit diameter. This law depends upon two parameters only, which were identified as the coverage time τ (i.e. the time required for the surface to be covered by erosion pits) and a characteristic pit diameter δ, which corresponds to the pits whose contribution to the coverage process is the highest. Scaling laws for pitting were derived accounting for both material properties and flow velocity, and a procedure to make pitting test results non-dimensional is proposed. The influence of the material on pitting test results was analyzed. It is shown that the damage is not correlated in simple terms with the elastic limit determined from conventional tensile tests and it is conjectured that other parameters such as the strain rate might play a significant role and should be included in the analysis. The effect of flow velocity on both parameters τ and δ was analyzed and a classical power law was found for the influence of the flow velocity on pitting rate for all three materials. Finally, some analysis and discussion is given concerning distributions of pit volume and pit depth. 相似文献
199.
Michel C. Boufadel Makram T. Suidan Albert D. Venosa 《Canadian Metallurgical Quarterly》2006,132(6):616-623
Bioremediation of oil spills on tidally influenced beaches commonly involves the addition of a nutrient solution to the contaminated region of the beach at low tide to stimulate the growth of indigenous oil-degrading bacteria. Maximizing the residence time of nutrients in the beach and subsequently their contact time with microorganisms is a main goal for successful bioremediation. Therefore, understanding the effects of the tide on water flow and solute transport in a beach is an essential task for designing a nutrient application strategy. We investigated these effects by conducting a tracer study in a laboratory beach simulating nutrient application on natural beaches. The study consisted of applying, at low tide, a conservative tracer solution onto the beach surface near the high-tide line and monitoring its movement in the beach subsurface. The tidal motion caused the applied plume to move downward and seaward. The downward movement occurred during rising tides, while the seaward movement occurred mainly during falling tides. The results indicate that nutrients should be applied at the high-tide line during low tides. Guidelines for scaling up the results to natural beaches are provided along with an example. 相似文献
200.
Masakazu Anpo Shinya Higashimoto Masaya Matsuoka Nurbosyn Zhanpeisov Yasushi Shioya Stanislaw Dzwigaj Michel Che 《Catalysis Today》2003,78(1-4):211-217
V-silicalite catalysts (VS-1 and VS-2) prepared by hydrothermal synthesis have been studied by ESR, XAFS (XANES and EXAFS) and photoluminescence spectroscopy. The in situ characterization of these V-silicalites shows that vanadium is present within the zeolitic framework as a highly dispersed tetrahedrally coordinated V-oxides, VO4 unit, having a short V=O bond length. Photoluminescence spectroscopy in static and dynamic mode, as well as XAFS studies allow to detect in the V-silicalites different V species than that present in V-HMS or V/SiO2, in terms of V=O bond length, vibrational energy,
bond angle and lifetime of the excited triplet state. It is suggested that the combined contribution of the neighboring Si---OH group attached to the VO4 unit and the zeolitic rigid framework structure of V-silicalites cause a more significant and pronounced effect on the chemical properties of the VO4 unit than the flexible structure of V-HMS or V/SiO2. Moreover, the dynamic quenching of the phosphorescence by the addition of reactant molecules such as NO or propane indicates that the V species in the excited triplet state can be expected to be the active sites for the photocatalytic reactions. 相似文献